Rotary tunneling machine having off-set head



Sept. 7, 1965 L. F. SCOTT ROTARY TUNNELING MACHINE HAVING OFF-SET HEAD 5 Sheets-Sheet 1 Filed DeG. 27. 1960 mr mm F V ms N n a M w Om ll .i\.\ lf \\i xmww ROTARY TUNNELING MACHINE HAVING OFF-SET HEAD Filed Dec. 27, 1960 L. F. SCOTT Sept. 7, 1965 5 Sheets-Sheet 2 INVENTOR.

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LOREN F. SCOTT BY Sept. 7, 1965 L. F. scoTT,

ROTARY TUNNELING MACHINE HAVING OFF-SET HEAD 5 Sheets-Sheet 4 Filed Dec,

INVENTOR.

1-. SCOTT LORE'N Sept. 7, 1965 1.. F. scoTT 3,205,014

I ROTARY TUNNELING MACHINE HAVING OFF-SET HEAD Filed Dec. 27. 1960 5 Sheets-Sheet 5 INV EN TOR.

LOREN 1-. SCOTT BY United States Patent 3,205,014 ROTARY TIJ'RWELING MAQHINE HAVING (EFF-SET IEAD Loren F. Scott, tlhicago, IlL, assignor to Terra-Form Footing (10., Chicago, IlL, a corporation of'Illinois Filed Dec. 27, 1960, Ser. No. 78,487 5 Claims. (Cl. 299-31) The present invention relates to a machine for forming tunnels, especially large diameter tunnels for use as storm drains and the like.

In a specific use thereof, the machine of the invention is employed to drive a thirteen foot diameter tunnel through earth, and is also employed to drive smaller lateral tunnels or spurs, such as seven, eight and ten foot diameter tunnels. Prior to the advent of the machine, such tunnels were usually formed manually by crews working with spades and shovels.

The machine is comprised essentially of a horizontal beam-like frame adapted to extend longitudinally of the tunnel, a rotatable excavating wheel of a diameter considerably larger than the frame journalled on the forward end of the frame in a plane perpendicular to the axis of the frame and with its axis adjacent and parallel to the frame axis, the wheel having excavating teeth on its front face for cutting a circular hole in the ground, a supporting structure for the frame and wheel comprising collar means slidably engaging about the frame and jacks extending horizontally outward from the collar means for engagement with the tunnel walls to secure the supporting structure in the tunnel, and wheel crowding means connected between the frame and the supporting structure for crowding the frame and wheel forwardly relative to the supporting structure when the latter is locked in the tunnel. Also, the frame includes a pair of depending jack means for supporting the frame in the tunnel so that the horizontal jacks can be released from the tunnel walls and the collars can be advanced on the frame when necessary.

The mode of operation of the machine is essentially as follows: After a vertical manhole shaft has been formed and the tunnel has been started by hand, the machine is lowered from the surface through the manhole into the tunnel. The front face of the wheel is engaged with the face of the tunnel and the jacks are actuated to level and aim the frame and the wheel in the tunnel for continuation of the tunnel to specifications. In general, the wheel is of the same diameter as the tunnel and the frame extends generally axially rearward therefrom. The collars are then advanced forwardly on the frame and the horizontal jacks are projected outwardly to gain a firm purchase on the tunnel walls, whereby said supporting structure is fixed in the tunnel. The wheel is set in operation and the crowding means are actuated to force the wheel and frame forwardly against the face of the tunnel to cut or excavate the earth. Preferably, a conveyor is provided on the frame for carrying excavated materials from the wheel to the rear end of the frame where the conveyor may discharge into muck cars or any other suitable means for removing the materials from the tunnel. As the wheel and frame are advanced, the same are accurately guided by said supporting structure. When the wheel and frame have been advanced to the limit accommodated between the supporting structure and the frame, the depending jacks on the frame are lowered to support the frame from the bottom of the tunnel. The jacks of the supporting structure are then retracted and the crowding means is actuated in the reverse direction to slide the supporting structure forwardly on the frame, whereupon the jacks are again actuated to gain a new purchase on the walls of the tunnel. After this, the depending jacks on the 3,235,014 Patented Sept. 7, 1965 ice frame are retracted, and the crowding means is actuated to again drive the wheel forwardly against the face of the tunnel. In this manner, the machine is advanced step-bystep to form the tunnel, and it may be employed with facility to form both straight and curved tunnels and to establish and maintain any specified tunnel grade.

The object of the invention, in general, is to provide a machine of the character described that is economical to manufacture and use, and that is highly eificient and practical for the purposes stated.

A more specific object of the invention is to provide such a machine wherein the axis of the frame and the supporting structure is offset from, preferably vertically below, the axis of rotation of the wheel to mitigate any tendency of the wheel drive means to rotate the frame and to provide for a stronger and more effective reaction point or purchase of the frame supporting structure.

Another object of the invention is to provide means for accurately aiming and guiding the frame and wheel, comprising a pair of longitudinally spaced collars slidably engaging about the frame, a pair of horizontal jacks extending outwardly in opposite direction from each collar, a jack extending downwardly from each collar and means interconnecting said collars, the jacks being selectively operable to aim the frame as desired and to afford a rigidly fixed frame support in any adjusted wall-engaging position of the jacks.

It is also an object of the invention to provide in a machine as described a materials discharge conveyor extending above the frame from the wheel to the rearward end of the frame, means articulately mounting the wheel and the conveyor on the frame for horizontal swinging movement, support means for the rearward end of the frame accommodating transverse horizontal movement of the same, and means for selectively moving the rearward end of the conveyor, thereby to accommodate a plurality of parallel muck removal means rearwardly of the machine and thereby to accommodate high speed operation of the machine for rapid formation of the tunnel.

Yet another object of the invention is the provision of a machine as described including a purchase or anchor jacks that are articulated to the frame for relative collapsing movement, whereby the jacks may be relatively collapsed on the frame to facilitate entry and removal of the machine from the tunnel.

Other objects and advantages of the invention will become apparent in the following detailed description. 7

Now, in order to acquaint those skilled in the art with the manner of making and using my tunneling machine, I shall describe, in connection with the accompanying drawings, a preferred embodiment of the machine and a preferred manner of making and using the same.

' machine, taken substantially on line 22 of FIGURE 1;

FIGURE 3 is an enlarged fragmentary cross-section of the machine through one of the frame supporting collar and jack assemblies, the view being taken substantially on line 3-3 of FIGURE 1;

FIGURE 4 is a fragmentary front elevation of the digging wheel, the view showing by shaded and unshaded annular areas the paths of the excavating blades and cutters;

FIGURE 5 is a plan view of one of the excavating blades;

FIGURE 6 is a plan view of one of the excavating cutters; FIGURE 7 is a side view of one of the excavating blades, the view being substantially on line 7-7 of FIG- URE 5;

FIGURE 8 is a side view of one of the excavating cutters, the view being generally similar to FIGURE 7;

FIGURE 9 is a fragmentary longitudinal section of the forward end of the machine and the excavating wheel; and

FIGURE 10 is a fragmentary perspective view of the wheel shell showing one of the mounting blocks for the blade and cutter carrying arms.

Referring now to the drawings, and particularly to FIG- URE 1, the preferred embodiment of my tunneling ma chine is shown as comprising an excavating wheel 29 a relatively small diameter frame 22 extending generally axially rearward from the wheel, a supporting and guiding structure 24 for the frame, supporting jacks 26 for the frame and a conveyor 28 mounted above the frame and extending from the wheel to the rearward end of the frame.

The frame 22 preferably comprises an elongate rigid steel tube, suitably about inches in diameter, having longitudinally extending guide tracks 30 on its upper and lower surfaces adjacent its opposite ends. At its forward end, as shown in FIGURES 2 and 9, the tube 22 rigidly mounts therein a short tubular bearing member 32 which extends through and is secured to a vertical frame plate 34 that is secured to the front face of the tube 22 perpendicular thereto. The bearing member 32 is disposed parallel to the tube axis but is eccentric thereto, and the same is preferably set vertically and centrally above the axis of the tube substantially to the full extent accommodated by the tube.

The axle 35 of the wheel 20 is rotatably mounted within the bearing member 32, the same being journalled therein by a pair of tapered roller bearings 38 engaging against conically countersunk wall portions in the opposite ends of the bore in the member, and being retained in association therewith by a nut 40 threaded onto the rearward end of the shaft and engaging against the rearward one of the bearings 38. Preferably, the member 32 is counterbored at its ends for reception of oil seals 42. Adjacent its forward end, the axle mounts a circular central wheel hub or disc 44 which is reinforced by a plurality of triangular radial gusset plates 46 secured to the shaft and the disc forwardly of the disc. On its rearward surface, the disc 44 mounts an internally toothed ring gear 48 by means of which the wheel 20 is rotated.

The wheel drive mechanism is mounted on and extends through the frame plate 34 above and preferably to one side of the tube 22, the mechanism comprising a pair of high torque electric motors 50, suitably 300 volt, cycle, 90 horsepower motors, a transmission or gear reduction unit 52 driven by each motor, and a pinion 54 secured to the output shaft of each unit 52 and engaged with the ring gear 48. This mechanism is especially adapted to drive a thirteen foot diameter wheel at a peripheral speed in the order of about to feet per minute, which I have found to be highly eflicient wheel speed.

The wheel per se, as best shown in FIGURES 2, 4 and 10, is comprised of the axle 36, the disc 44, a concentric annular shell 56 and a plurality of radial arms 58 extending between and secured to the front or forward surfaces of the disc and shell. In the preferred embodiment, four equally spaced arms 58 divide the wheel into four equal segments or quadrants. At its inner end, each arm rests on the wheel axle intermediate two adjacent gusset plates 46 and is secured to the disc 44 by a pair of radially spaced brackets or clamps 66. At its outer end, each arm extends into and is secured within a respective pillow block structure 62 which is secured to the shell 56. The shell 56 comprises a cylindrical wall 64 which is reinforced at its forward edge by a bead 66, a radial flange 68 at the rearward edge of the wall and a plurality of generally radial fins 70 secured, as by welding, to the inner surface of the wall 64 and the front face of the flange 68. In the embodiment illustrated herein, the shell is thirteen feet in diameter and is constructed from identical segments or quadrants in accordance with the division of the Wheel by the arms 58. Each end of each segment is provided with a triangular gusset 72, by means of which the seg ments are bolted together (as indicated in FIGURE 10) or otherwise detachably connected together. Each pillow block 62 is preferably located at each juncture of the wheel segments, with one part of each block being secured to a respective wheel segment. By virtue of the segmentalization of the wheel, the wheel may be assembled and disassembled in the tunnel to facilitate entry and removal of the machine, and to facilitate replacement and repair of the wheel without removing the machine from the tunnel. The fins 70 are inclined both radially inward and in the direction opposite the direction of wheel rotation as they extend toward the flange 68, thereby to move excavated material toward the rearward face of the shell and to carry excavated material upwardly from the bottom of the wheel to a discharge point as the wheel rotates.

To effect excavation of earth materials, the wheel is provided on its front face with a plurality of cutting or excavating elements which are secured on the arms 58 and project forwardly therefrom. These elements are of two types, which may be identified respectively a blades and cutters. The blades are shown in FIGURES 4, 5 and 7 as being mounted on diametrically aligned ones of the arms 58, each blade comprising a mounting post 74 secured, as by welding, to the respective arm 58 and extending diagonally forward therefrom in the direction of wheel rotation, and a blade tip 76 mounted on the outer end of the post. Each blade tip at its outer end includes a cutting edge of predetermined width, and the blade is preferably tilted in a radially inward direction to define a clearance angle in the order of about 5 degrees. This clearance angle may be incorporated in the blade tip, in which case the post may extend perpendicular to the arm 58, or may be provided by tilting the post relative to the arm 58 by the indicated angle.

The blade posts and tips that I employ are standard articles of commerce, namely, trencher teeth, and the manufacturers thereof specify installation of the same at a cutting angle from 20 to 35 degrees. As thus installed, I have found that the blades will accommodate tunneling at the rate of about 26 to 28 feet per eight-hour shift, that the blades have to be reversed at the end of four hours and replaced at the end of each eight-hour shift, and that the blades or teeth chatter or cause the wheel to chatter, especially when endeavors are made to increase tunneling speed. In contrast to the manufacturers recommendations and the accepted standards of the art, I have installed the teeth or blades in my machine in such manner as to have a much higher cutting angle, the specific angle being 47 /2 degrees as indicated in FIGURE 5. By virtue of this increase in cutting angle, I have eliminated blade and wheel chatter, have increased tunneling speed to 40 feet per eight-hour shift and have increased blade life by twenty times. Specifically, I have reduced blade cost from about $2.00 per foot of tunnel to about 10 cents. Also for a given tunneling footage, I have decreased power requirements by thirty to forty percent. In the preferred structure, the blade posts are all secured to the respective arm 58 at the same angle, and the arms are individually rotatable to vary the cutting angle of all of the blades to achieve best results in a particular environment.

To facilitate blade installation, I mount the blades on the arms in such maner that all of the blades collectively span the space between the disc 44- and the shell 56 without significant overlapping or duplication of effort. Specifically, I mount the blades on each post on centers spaced radially by a distance substantially equal to the product of the width of the blades and the number of blade carrying arms, and I stagger the blades on each arm relative to the blades on the other arms. In the preferred structure illustrated, this results in the blade being spaced apart by the width of the blade. Consequently, as depicted by the shaded and unshaded annuluses in FIGURE 4, the blades on the upper vertical arm 58 excavate certain areas of the tunnel face (the shaded annular areas) and the blade on the lower vertical arm 58 excavate the intermediate (unshaded) annular areas.

To facilitate excavation of earth, especially hard earth materials, I also provide cutters on the face of the wheel 20, the cutters being mounted on the alternate ones of the arms 58 and each comprising a mounting block 78 secured to the respective arm and a cutter or cutting tip 80 replaceably mounted in the block, the cutter suitably comprising teeth tipped with Carboloy or other hard tip material. The cutters are mounted on the respective arms 58 on centers spaced apart essentially the same distance as, and are staggered in essentially the same relation as, the blades 78, each cutter being located in the same radial distance from the hub as the inner edge of one blade and the outer edge of another blade. Specifically, the cutters on the right hand horizontal arm in FIGURE 4 are aligned circumferentially with the inner edges of the respective blades on the upper vertical arm and the outer edges of the respective blades on the lower vertical arm, and the icutters on the left hand horizontal arm are aligned circumferentially with the outer edges of the respective blades on the upper vertical arm and the inner edges of the respective blades on the lower vertical arm. Each of the cutting tips 80 is projected further forward from the face of the wheel than the excavating blade 76, so that the cutters cut spaced circular grooves in the tunnel face in advance of the blades (see FIGURE 7) and the blades subsequently chip or chisel out the material between the grooves thereby to afford a highly efl'lcient excavating process.

As the cutters and blades remove earth materials from the tunnel face, the material falls downwardly and rearwardly into the interior of the wheel shell at the bottom of the wheel. The fins 70 then contact this loose material, movingly guide it into the shell adjacent the flange 68 thereof, and commence to carry the material upwardly as the wheel continues to rotate. After any given fin 70 has passed a horizontal position and is moved further upwardly to a point where gravitation-a1 influence outweighs centrifugal force, the material carried by the fin commences to gravitate downwardly out of the shell.

To catch the material thusgravitating from the shell, I have provided the conveyor 28, which is preferably in the form of an elongate endless belt 82 mounted on conventional rollers 84 carried by a conventional supporting frame 86. The belt, which may if desired be provided with material impelling transverse blades or buckets 88, is driven by means of a motor 90, preferably a rotary hydraulic motor, drivingly connected to the rearward one of the belt supporting rollers 84. At the forward or wheel end thereof, the conveyor project into the interior of the wheel below the point of material discharge of the fins 70. At this end of the conveyor, the roller 44 is journalled in bearings 92 which are secured to opposite ends of a supporting plate 94 that is articulately mounted on the frame 22 to accommodate horizontal swinging movement of the conveyor, the articulated connection suitably comprising an upright pivot pin 96 pivotally joining the plate 94 and a complemental supporting plate mounted on the machine frame. Adjacent the rearward end of the conveyor, a second conveyor supporting means 98 is provided to accommodate transverse horizontal movement of the rearward end of the conveyor through a wide arc, whereby the conveyor may be accurately aligned with the material removal means and may discharge selectively into a plurality of parallel removal means, such for example, as into muck cars traveling on parallel sets of mine car rails that are installed in the tunnel rearwardly of the machine as the tunnel is being formed by the machine, whereby the machine may be operated at full speed and is not unduly restricted in operation by inadequate material discharge and removal means. The structure 98, in the illustrated embodiment of the machine, may comprise a parallelogram linkage including a horizontal bar 100 secured to the frame 22 of the machine, and a pair of upright links 102 pivoted at their ends to the opposite ends of the bar and the opposite sides of the conveyor frame 86. To effect horizontal swinging movement of the conveyor, I provide a hydraulic cylinder 104 which extends between the frame 22 and one of the links 102.

To support and guide the frame 22 and the wheel 20, I have provided the supporting structure 24, which is best shown in FIGURES l to 3. As illustrated, this structure preferably comprises a pair of longitudinally spaced collars 106 which encircle and slidably, but non-rotatably, engage about the main frame tube 22. Each collar suitably comprises a fabricated structure including peripheral wall members generally defining an octagon, a pair of generally annular end plates encircling the tube 22, and two sets of roller assemblies which are secured to the peripheral wall members of the collar at the top and bottom of the tube and engage against the guide tracks 30 to support the tube on the collar and prevent relative rotation of the two. Preferably, each roller assembly comprises four horizontally disposed rollers 108, there being two longitudinally spaced rollers to each side of the respective guide 30, and a pair of longitudinally spaced vertically disposed rollers 110 which ride on the radially outward surface of the respective track 30, the vertically disposed rollers causing the tube and collar mutually to support one another and the horizontally disposed rollers preventing relative rotation of the tube and collar. Secured to the peripheral wall members of each collar are three jack structures, namely, a pair of oppositely extending horizontal jack structures 112 and a vertically depending jack 114, all of which project radially from the collar. Each jack structure comprises a telescopic assembly of rigidifying and protective pipes or tubes within which a hydraulic jack is installed. As shown for one of the hori zontal jack structures in FIGURE 3, each jack may cornprise an outside protective tube 116, an inside tube 118 telescopically mounted in the outside tube and having an outer end wall 120 provided with means, such as intersecting flanges 121, for bitingly engaging into the wall of the tunnel, and a hydraulic jack 122 disposed within the interior of the two tubes. To accommodate a degree of flexing of the protective pipe or tube assembly without creating a source of damage to the jack 122, I pivotally connect the jack to the two tubes or pipes. Specifically, the body or cylinder of the jack may be pivotally connected by a =clevis assembly 124 to an inner end wall of the outside tube 116, while the piston of the jack may be similarly connected by a clevis assembly 126 to the outer end wall 120 of the inside tube or pipe 118, a hole 123 being provided in the wall of the pipe 118 to accommodate installation of the pivot pin of the assembly 126. Holes are similarly provided adjacent the base or inner end of the outside pipe to accommodate passage of hydraulic supply conduits 130 for the jack 122.

In the case of at least the horizontally extending jack structures 112, I provide means accommodating relative collapsing of the jacks with respect to the main frame 22, thereby to facilitate entry of the machine into a tunnel and removal of the same from the tunnel. Specifically, I pivotally mount the assembly of the pipes 116- 118 and the jack 122 on the outer end of a rigid tubular base member or portion 132 which is rigidly secured at its inner end to the collar 106. At the outer end of the base portion 132 and the inner end of the pipe assembly 116- 118, I provide the complemental parts of a flange-type coupling which is generally conventional, except that each of the two flanges is provided with a generally radially extending hinge leaf 134 through which a pintal pin 136 passees, whereby the pipe 116 is hingedly connected to the base member 132 to permit folding of the jack structure intermediate its ends (as indicated in dotted lines in FIG- URE 3) when the normal flange coupling bolts 138 are removed.

To complete the frame supporting structure 24, I provide rigid struts 140 between the normally stationary or rigid portions of the horizontal jacks 112 on both sides of the frame 22 thereby to connect the two collars 196 and render the same, in effect, a unitary supporting structure for the tubular frame 22, the said structure supporting the frame at longitudinally spaced points and by virtue of the six jacks 112 and 114 being capable of supporting the frame in substantially any tunnel environment and of guiding or aiming the frame and the wheel in a most accurate manner to maintain grade, hold the wheel on course, and accommodate formation directly by the machine of even curved portions of a tunnel.

As previously described herein, the supporting structure, when positioned forwardly on the frame, supports the frame and wheel for forward movement of the wheel. When the Wheel has been advanced to the extent accommodated by the guide tracks 30, the jacks 112 and 114 are retracted and the supporting structure is advanced to the forward end of the frame, whereupon the jacks may be extended to gain a new purchase on the tunnel walls, and the wheel may again be advanced. By virtue of the hydraulic jacks a very firm foothold is secured in the tunnel to retain the frame and wheel in proper excavating position. Also, by supporting the wheel eccentrically of the tube 22, and thus of the supporting structure 24, the tendency of the wheel to rotate the frame and supporting structure is greatly minimized and the supporting structure firmly retains the frame in excavating position. For the purpose of moving the frame and the supporting structure relative to one another as above described, I provide a pair of double-acting hydraulic crowding jacks 142, one on each side of the frame, which extend diagonally from the rearward horizontal jack structures 112 to the central portion of the tubular frame 22, the jacks being pivotally connected to the respective members at their opposite ends. As .is apparent, the jacks 142 may be extended to crowd the wheel 20 against the face of the tunnel and may be retracted to pull the supporting structure forwardly on the frame.

During this latter movement, while the jacks 112 and 114 are released from the tunnel walls, it is desirable to provide means for temporarily supporting the frame 22, or more properly to provide means for assisting the wheel in supporting the frame. To this end, I provide the two longitudinally spaced vertically depending jacks 26 on the frame, both of which are substantially the same as the jacks 114. In fact, the jacks 114 may be omitted from the machine if the horizontal jacks 112 are strong enough to hold the machine, as in machines having wheels smaller than that described for the illustrated embodiment of the invention. In such case the jacks 26 may be employed to assist the jacks 112 in leveling and aiming the wheel, whereafter the jacks 26 may be retracted to facilitate advance movement of the wheel.

For operating and controlling all of the described inst-rumentalities, i.e., the hydraulic units including the motor 90, the jack 104, the supporting jacks 112, 114 and 26, and the crowding jacks 142, and the electric motors 50, I provide a control system comprising a control panel 144 mounted on the central portion of the tubular main frame 22 and a power pack. 146 telescopically mounted within the rearward end portion of the tube. The power pack 146 comprises a base 143 slidably engaging within the tube 22 as a chord of the tube, an electric control panel 150 mounted on the rearward end of the frame, an electric motor 152 mounted on the frame and drivingly connected to three hydraulic pumps 154, 156 and 158 aligned axially therewith, and a fluid reservoir 166 on the front end of the frame from which the pumps are supplied. The pumps 154 and 156 are of high output capacity, such as ten gallons per minute, and are employed for supplying fluid under pressure to all of the described hydraulic units, and to auxiliary hydraulic equipment when such is employed in the tunnel adjacent the machine. The pump 158 on the other hand is a relatively low capacity constant pressure pump, such as a one gallon pump having a pressure regulator in the output line thereof. This pump is employed for controlled crowding of the wheel at constant pressure against the face of the tunnel. As will be appreciated, the power pack is thus mounted within the tube 22 to be protected from damage thereby, and yet may readily be slid out of the tube to an accessible position when inspection or repair is necessary.

The control panel 144 includes a hydraulic fluid header 152 to which fluid is supplied from the pumps and a plurality of control valves 16-!- for selectively controlling the supply of fluid to the described hydraulic units. With the exception of the valve for supplying fluids to the conveyor motor 90, all of the valves are normally closed three-way valves for selectively supplying fluid to one or the other end of the hydraulic jack supplies thereby. Preferably, the crowding jacks 142 are simultaneously supplied with fluid and all of the other jacks are individuallycontrolled. The control panel also includes a valve 166 for controlling supply of fluid at constant pressure from the pump 158 to the crowding jacks 142, whereby the crowding jacks are simultaneously operable in the wheel crowding direction from either or both of the low capacity pump 158 and the high capacity pump 154 and 156, and whereby the jack-s 142 are adapted to be retracted at relatively high speed by fluid supplied from the pumps 154 and 156, thereby to move the supporting structure 24 forwardly on the frame. The particular purpose of the pump 158 and the valve 166 is to crowd the wheel forwardly at relatively low speed and constant pressure, which I have found results in optimum excavation of earth and increases the useful life of the digging instrumentalities, i.e., the blades 76 and the cutters 80.

In addition, the control panel 144 includes suitable electric switches (not shown) for controlling operation of the pump motor 152 and the wheel drive motors 50. Consequently, an operator standing adjacent the panel 144 has complete control over the machine and is able to observe the entirety of its operation, whereby the single operator may effect manipulation of the machine in the manner described to form tunnels to exacting specifications.

From the foregoing, it is to be appreciated that I have provided a tunneling machine comprising a supporting structure and a digging wheel which are alternatively movable step-by-step to cause the wheel to dig a tunnel, the supporting structure being offset from the wheel and so constructed as to afford a firm and accurate guide for advancement of the wheel, the machine including precisely operated crowding means for advancing the wheel and the wheel including cutting instrumentalities for performing an extremely efficient excavating function. Also, the machine includes means for insuring rapid and continuous removal of excavated material to facilitate high speed operation of the wheel and rapid formation of a tunnel. Furthermore, the wheel is constructed of detachable segments and the supporting structure is partially collapsible, or can be dismantled, to facilitate entry and removal of the machine from a tunnel, and to facilitate the replacement or repair of a wheel in the tunnel without necessity for removal of the machine from the tunnel. Thus, I have illustrated that all of the objects and advantages of the invention are attained in a convenient, economical and practical manner.

While I have shown and described what I regarded to be the preferred embodiment of my invention, it is to be appreciated that various changes, rearrangements and modifications may be made therein without departing from the scope of the invention, as defined by the apended claims.

I claim:

1. A tunneling machine comprising a longitudinally extending main frame, supporting means slidably engaged with said frame, frame crowding means operatively connected to said frame and said supporting means for sliding the same relative to one another, an excavating wheel of a diameter larger than the lateral dimensions of said frame rotatably mounted on said frame at one end thereof, and means on said frame engaging said wheel for rotating said Wheel relative to said frame, the axis of rotation of said wheel being disposed parallel to but offset from the longitudinal axis of said frame to mitigate rotation of said frame by the last-named means when said wheel encounters resistance to rotation.

2. A tunneling machine comprising a longitudinally extending beam-like main frame, supporting means for said frame comprising collar means slidably engaging about said frame, a pair of longitudinally spaced laterally extending horizontal jacks secured to said collar means on each side of said frame and a pair of longitudinally spaced jacks secured to and depending downwardly from said frame, said jacks being selectively expansible and contractable to secure said collar mean-s fixedly in a tunnel and to accommodate sliding movement of said collar means on said frame, double-acting frame crowding jacks connected at their opposite ends to said frame and said collar means, said crowding jacks being operable to crowd said frame forwardly when said collar means is secured in a tunnel and to move said collar means forwardly on said frame when said horizontal jacks are freed from the tunnel and said depending jacks support said frame, an excavating wheel rotatably mounted on said frame perpendicular to the axis of said frame, said wheel being of a diameter larger than the lateral dimensions of said frame and said supporting means when said horizontal jacks are freed from the tunnel, and means on said frame engaged with said wheel for rotating said wheel relatively to said frame, the axis of rotation of said wheel being disposed parallel to but offset upwardly from the longitudinal axis of said frame to mitigate rotation of said frame by the last-named means when said wheel encounters resistance to rotation and to cause said latera'lly extending jacks to maintain a firm purchase in the tunnel walls.

3. A tunneling machine comprising a longitudinally extending main frame, supporting means slidably engaged with said frame, double-acting crowding means connected at its opposite ends to said frame and said supporting means for sliding the same relative to one another, an excavating wheel of a diameter larger than the lateral dimensions of said frame rotatably mounted on said frame at one end thereof, means on said frame engaged with said wheel for rotating said wheel relative to said frame, the axis of rotation of said wheel being disposed parallel to but offset upwardly from the longitudinal axis of said frame to mitigate rotation of said frame by the last-named means when said wheel encounters resistance to rotation, a generally longitudinally extending conveyor disposed above said main frame and extending from the interior of said wheel to adjacent the oppo site end of said frame, said conveyor being articulately mounted for horizontal swinging movement on said main frame at the end thereof adjacent said wheel, and supporting means for said conveyor adjacent the opposite end of said frame accommodating transverse horizontal movement of the rearward end portion of said conveyor.

4. A tunneling machine comprising a longitudinally extending main frame, supporting means slidably engaged with said frame, frame crowding means operatively connected to said frame and said supporting means for sliding the same relative to one another, an excavating wheel of a diameter larger than the lateral dimensions of said frame rotatably mounted on said frame on an axis parallel to but offset from the longitudinal axis of said frame, means on said frame engaging said wheel for rotating said wheel relative to said frame, and a plurality of jack structures extending laterally outward from said supporting means and engageable with the tunnel wall, each jack structure comprising a tubular mounting section rigidly secured at one end to said supporting means adjacent said frame and extending laterally outward therefrom, a bolting flange on the outer end of said mounting section, a first tubular housing section extending axially outward from said mounting section and having a complementary bolting flange on its inner end, said bolting flanges being pivotally connected together and adapted for reception of bolts to fixedly secure said sections together in axial alignment, a second tubular housing section telescopically mounted in said first housing section for slidable movement axially thereof, said first housing section having an end wall at its inner end and said second housing section having an end wall at its outer end, and a double-acting jack confined within said housing sections and pivotally connected at one end to one of said end walls on a first axis transverse to said tubular sections and pivotally connected at its opposite end to the other end wall on a second axis transverse to said tubular sections and at right angles to said first axis.

'5. A tunneling machine comprising a longitudinally extending main frame, supporting means for said frame comprising collar means slidably engaging about said frame and jack means normally extending laterally outward from said collar means, frame crowding means operatively connected to said frame and said supporting means for sliding the same relative to one another, an excavating wheel of a diameter larger than the lateral dimensions of said frame rotatably mounted on said frame on an axis parallel to but offset from the longitudinal axis of said frame, and means on said frame engaging said wheel for rotating said wheel relative to said frame, said jack means each comprising a laterally outwardly extending mounting section rigidly secured to said collar means, an extensible and contractable housing section pivotally mounted on said mounting section, said housing section comprising a pair of relative extensible and contractable parts, and a double-acting jack mounted in said housing section and operatively connected at its opposite ends to respective ones of said parts, the twosection assembly accommodating a short jack not susceptible to bending and the pivotal mounting of said housing section accommodating collapsing of the two sections relative to their normal lateral extension.

References Cited by the Examiner UNITED STATES PATENTS 1,855,421' 4/32 Ross 198-425 X 2,103,530 12/37 Henry 60-52 2,303,490 12/42 Nelson 198125 2,745,253 5/56 Towler et al. 60-97 2,75 6,03 6 7/56 McIntyre 299-5 6 2,811,341 10/57 Robbins. 2,833,531 5/58 Joy. 2,864,601 12/ 58 McCarthy et al. 2,946,578 7/ 60 De Smaele. 2,955,810 10/ 60 McWhorter. 3,061,287 10/ 62 Robbins.

FOREIGN PATENTS 843,581 8/62 Great Britain.

BENJAMIN HERSH, Primary Examiner.

JACOB L. NACKENOFF, Examiner. 

1. A TUNNELING MACHINE COMPRISING A LONGITUDINALLY EXTENDING MAIN FRAME, SUPPORTING MEANS SLIDABLY ENGAGED WITH SAID FRAME, FRAME CROWDING MEANS OPERATIVELY CONNECTED TO SAID FRAME AND SAID SUPPORTING MEANS FOR SLIDING THE SAME RELATIVE TO ONE ANOTHER, AN EXCAVATING WHEEL OF A DIAMETER LARGER THAN THE LATERAL DIMENSIONS OF SAID FRAME ROTATABLY MOUNTED ON SAID FRAME AT ONE END THEREOF AND MEANS ON SAID FRAME ENGAGING SID WHEEL FOR ROTATING SAID WHEEL RELATIVE TO SAID FRAME, THE AXIS OF ROTATION OF SAID WHEEL BEING DISPOSED PARALLEL TO BUT OFFSET FROM THE LONGITUDINAL AXIS OF SAID FRAME TO MITIGATE ROTATION 